Optoelectronics is a rapidly expanding technology that is an important component in modern communications systems wherein it is desired to transmit vast amounts of data over long distances in a short period of time. With the increasing commercial applications for optoelectronic systems, there is a need to develop cost effective and precise manufacturing techniques for assembling optoelectronic modules (e.g., optical subassemblies, fiber-optic cable repeaters, transmitters, etc.).
Transmitters used in optical fiber communications systems typically require a package containing a semiconductor laser coupled to an optical fiber that extends from the package. A major challenge in constructing such transmitters is in forming optical subassemblies which are hermetically sealed and for which the light emitting device operates at low temperatures. Hermetic sealing and low temperature operation are required in some applications to increase performance and lifetime of the light emitting device and transmitting package.
One problem with hermetic sealing in optical subassemblies is the poor yield due to insufficient sealing at a glass/metal interface. Typical interfaces are formed using parallel seam welding which provides inconsistent sealing that may leave gaps at the interface. Another problem with hermetic sealing is that the device structure provides no feature or lid to assist in the external alignment of the light emitting device and the optical fiber. Still another problem is the limited space within the optical subassembly to position other optical components such as a lens, an optical isolator, or the like. While hermetic sealing is a problem in the present art, low temperature operation is the major challenge. The main problem to be solved is to achieve a low thermal resistance between the laser or light generator and a heat spreader designed and mounted to carry heat from the laser or light generator.
It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.
It is an object of the present invention to provide a new and improved optical subassembly.
Another object of the present invention is to provide a new and improved support structure for mounting an optical device.
A further object of the present invention is to provide a new and improved hermetically sealed optical subassembly with greater thermal conductivity (i.e. improved thermal stability) and improved coupling to external optical components, such as optical fibers and the like.
A further object of the present invention is to provide a new and improved optical subassembly that is simpler to manufacture and assemble with improved optical alignment.